Apparatus for ageing quicklime



Feb. 1, 1966 HlDEO SASAKI APPARATUS FOR AGEING QUICKLIME ,Filed June 6, 1963 INVENTOR H/DEO SASAKI' BY W 1? 2mm ATTORNEYS United States Patent 3,232,714 APPARATUS FOR AGEING QUICKLIME Hideo Sasaki, Meguro-ku, Tokyo-to, Japan, assignor to Onoda Cement (10., Ltd., Onoda, Japan Filed June 6, 1963, Ser. No. 285,996 Claims priority, application Japan, Aug. 8, 1962, 37/ 32,676 4 Claims. (Cl. 23-279) The present invention relates to an apparatus for ageing quicklime. More particularly, the present invention is concerned with an apparatus for ageing quicklime, where rotary kilns are used and the product discharged from the rotary kiln is maintained at a high temperature for a period of time before cooling so as to complete the decomposition of the remaining calcium carbonate.

According to the prior art manufacture of quicklime by the use of a rotary kiln, the calcined limestone is discharged directly and cooled. As a result the calcination of the lime cannot be finished because the undecomposed calcium carbonate remains in the product.

It is an object of the present invention to provide an apparatus attached to the rotary kiln that calcines limestone continuously for keeping the product from the rotary kiln hot for a time and thereby finishing the calcination. A further object of the invention is to provide an apparatus for ageing quicklime comprising a means for receiving the lime calcined from a rotary kiln, keeping it hot for a certain period and cooling the aged lime.

The invention is further illustrated in the accompanying drawing wherein FIG. 1 shows a vertical section of one form of apparatus in accordance with the invention, and FIG. 2 shows the cross section taken on the line 11-11 in FIG. 1.

In accordance with the present invention the apparatus for ageing is located right under the exit of a rotary kiln 9. The apparatus of the invention is essentially comprised of an annular bottom plate 4, a vertical annular rotary vessel 7, cover 11, and a connecting cylinder 12 for connecting the rotary vessel 7 with the exit of the rotary kiln 9. The bottom plate 4 is an annular plate of perforated part 2 for cooling and unperforated part 3, and receives the product from the rotary kiln at the front end of unperforated part 3 and exhausts the aged lime at the back end of perforated part 2. The vertical rotary vessel 7 has an outer cylinder and inner cylinder 6 and is placed on the bottom plate 4 so as to be rotated horizontally around the same axis. The outer cylinder 5 and inner cylinder 6 are connected to each other outside frame 13 and inside frame 13 extending in the radial direction and fixed at the bottom of the cylinders. The outside frame 13 has many rollers 16 at the back thereof, the rollers 16 moving on a fixed rail 17, and gear tooth 14 at the circumference thereof with gear tooth 14 interlocking with a motive gear 15.

An annular covering plate 11 is fixedly provided on the upper of the vertical rotary vessel. The connecting cylinder 12 is provided to the annular covering plate 11 directly over the front end of the unperforated part 3. The connecting cylinder 12 being connected with the cover at the exit of the rotary kiln 9 to lead the calcined lime into the vertical rotary vessel 7. Hopper 18 extends under most of the back or perforated part 2. The hopper 18 has a duct 8 delivering cooling air. At the rear of outlet 19 adjacent to the back end of the perforated part 2, a discharge chute 20 is provided. The discharge chute 20 discharges the product lime aged and cooled onto a belt conveyer 22 through a discharging means 21. The outer and inner cylinders 5, 6 have a refractory lining.

In the operation of this apparatus the hot product discharged continuously from the rotary kiln 9 is supplied to the vertical rotary vessel 7 rotating slowly to form a uniform layer on the stationary bottom plate 4. This charge layer is slowly moved toward the outlet 19 by the inside radial frame 13', whereby the charge layer is aged on the unperforated part 3. This results in the complete decomposition of the remaining calcium carbonate, and the aged charge is cooled on the perforated part by cooling air supplied from the duct 8. The thus aged and cooled product is discharged continuously from the discharge chute 20.

It is apparent from the illustration described as above that in the present invention an excellent quicklime can be obtained through the provision of the ageing means whereby calcination of the lime is completed.

What I claim is:

1. An apparatus for ageing quicklime comprising a stationary annular bottom plate having an unperforated first half, a perforated latter half and an outlet at the end of said latter half, a vertical annular rotary vessel comprising an outer cylinder and inner cylinder supported for rotation over said bottom plate concentrically thereto inside radial frame means connecting the base portions of said cylinders, a fixed cover for covering the top of said rotary vessel, a charge cylinder for delivering calcined lime from a rotary kiln to said unperforated half of said bottom plate, means for supplying cooling air, said means provided under said perforated part, means for discharging aged lime, said means provided at the back of said outlet, and means for rotating said rotary vessel relative to said bottom plate horizontally around a common vertical axis.

2. The apparatus of claim 1 wherein said vertical annular rotary vessel is'supported by an outside frame and inside frame, said outside frame having gear teeth and rollers and said inside frame being arranged at intervals in the radial direction.

3. The apparatus of claim 1 wherein said means for supplying cooling air is a hopper having a duct for cooling air and receiving the lime passed through said perforated part.

4. The apparatus of claim 1 wherein said means for discharging aged lirne is a discharge chute having discharging means for discharging aged lime onto a conveying means.

References Cited by the Examiner UNITED STATES PATENTS 520,369 5/ 1894 Melville 23-284 FOREIGN PATENTS 694,430 7/ 1953 Great Britain.

MORRIS O. WOLK, Primary Examiner. JAMES H. TAYMAN, JR., Examiner. 

1. AN APPARATUS FOR AGEING QUICKLIME COMPRISING A STATIONARY ANNULAR BOTTOM PLATE HAVING AN UNPERFORATED FIRST HALF, A PERFORATED LATTER HALF AND AN OUTLET AT THE END OF SAID LATTER HALF, A VERTICAL ANNULAR ROTARY VESSEL COMPRISING AN OUTER CYLINDER AND INNER CYLINDER SUPPORTED FOR ROTATION OVER SAID BOTTOM PLATE CONCENTRICALLY THERETO INSIDE RADIAL FRAME MEANS CONNECTING THE BASE PORTIONS OF SAID CYLINDERS, A FIXED COVER FOR COVERING THE TOP OF SAID ROTARY VESSEL, A CHARGE CYLINDER FOR DELIVERING CALCINED LIME FROM A ROTARY KILN TO SAID UNPERFORATED HALF OF SAID BOTTOM PLATE, MEANS FOR SUPPLYING COOLING AIR, SAID MEANS PROVIDED UNDER SAID PERFORATED PART, MEANS FOR DISCHARGING AGED LIME, SAID MEANS PROVIDED AT THE BACK OF SAID OUTLET, AND MEANS FOR ROTATING SAID ROTARY VESSEL RELATIVE TO SAID BOTTOM PLATE HORIZONTALLY AROUND A COMMON VERTICAL AXIS. 